Just to share my response to a comment on the PLOHSS project from somebody who claimed that:

Any form of APC was unacceptable

All APCs would be viewed as vanity publication

Me:
I think the "vanity publishing" argument is totally fallacious; it's clear that the review process would be completed utterly independently well before any consideration of finance would be made. You'll get your accept/reject email on the basis of the article, then we can talk money. Sure, there are predatory OA journals on the APC model. I hold that the current model is wholly predatory, though, when based on subscriptions, so pick the lesser of two evils and trust (when we have the requisite respected academic capital at the top) that we'll do things right.

Furthermore, as I said by email to the commenter, I have long held an opposition to author pays models (see any of my publications and also my own journals). However, I have come to conclude that, at a practical, extreme high-volume model (such as that operated by PLOS), there is no way that freely given/volunteered labour can cover all the necessary tasks in a fair manner that will pose a serious threat to the existing model. In fact, it might be ethically dubious (under the pragmatic conciliations we must make to the capitalist system) to expect this to be undertaken without some form of recompense. There *is* labour involved in publication; it's not as much as publishers claim, but it is still work and people need to eat.

The compromise that I am willing to make on this front is to establish a strictly non-profit organization that will waive any APCs on request. In short: we will operate on a goodwill model that purely sustains the cost of employing a low number of staff on a permanent basis to undertake the publishing side of the work. My eventual plan/hope is that if enough institutions subscribe on bulk (to waive fees for their researchers), we can then waive all author fees once costs are covered.